I solved my problem by changing the compression method in the initramfs.conf file to xz ( COMPRESS=xz) ,updating initramfs and updating GRUB after. Commands: -> sudo update-initramfs -u -k version in my case: sudo update-initramfs -u -k 5.15.86-rt56 ->sudo update-grub Important to say that I'm using version 5.15.86-rt56 now. Also, I noticed before solving the problem that the initrd.img-"version"-rt"x" was a big file with around 700 MB size, after changing the compression method and updating initramfs it is with 56,1 Mb now. I hope this helps, Michel
